Machine for embedding dowels in road paving



Dec. 18, 1962 R. HoucK l MACHINE FOR EMBEDDING DOWELS IN ROAD PAVING Filed NOV. 24, 1959 ROY L. HCUCK United States Patent Otitice 3,068,766 Patented Dec. 18, 1962 3,068,766 MACHINE FOR EMBEDDING DOWELS IN ROAD PAVING Roy L. Houck, 1585 NE. 20th St., Salem, Oreg. Filed Nov. 24, 1959, Ser. No. 855,154 1 Claim. (Cl. 94-51) This invention relates to the construction and paving of roadways and similar surfaces with concrete or other cementitious material and more particularly to a machine for embedding successive series of lubricated dowels in the paving material in parallel spaced relation to each other in each series transversely of the roadway, and to a method of controlling the natural cracking of concrete paving into sections and the subsequent lineal movement of the sections relative to each other dueto heat expansion and other relative displacements and misalignments due to frost heaving and other natural causes.

The principal objects of the invention are:

To provide a self-propelled machine for embedding successive series of lubricated dowels in the paving material at predetermined intervals lengthwise of the roadway with the doWels in parallel spaced relation to each other in each series transversely of the roadway.

To provide a machine of the character described which is of simple, efcient, durable construction, requiring no particular skill on the part of an operator in controlling its foolproof, rapid, and therefore time and labor saving, operation.

To provide a new and novel method of controlling the natural cracking of the paving material under temperature variations into predetermined accurately defined sections and controlling subsequent lineal movement of the sections relative to each other.

The foregoing and other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawing forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE l is a side elevational view of a dowel setting machine made in accordance with my invention and shown operatively mounted upon parallel rail-like side forms of a concrete highway under construction.

FIGURE 2 is a sectional rear elevational view taken approximately along the line 2-2 of FIGURE 1.

FIGURE 3 is a sectional detail view taken approximately along the line 3-3 of FIGURE 2; and

FIGURE 4 is a fragmentary elevational view of the left-hand end of FIGURE 2 drawn to an enlarged scale for clearness of illustration.

With continuing reference to the drawing, wherein like reference characters designate like parts, reference numeral 1 indicates generally a carriage comprising parallel longitudinal side frame members 2 and 3 interconnected at their ends -by transverse members 4 and 5 and supported by a pair of power driven front wheels 6 secured to an axle 7 and a pair of idling rear wheels 8 rotatable about an axle 9. The front axle 7 is driven by a sprocket chain 10, power transmission means 11 and engine 12 mounted upon the carriage.

Both pairs of wheels 6 and 8 are flanged as shown and thereby adapted for guided rolling engagement with parallel rail-like side forms 14 and 15 of a concrete highway under construction and between which forms green concrete 16 is poured and leveled.

superimposed upon the carriage, at approximately the center thereof, is a transverse frame indicated generally at 18 comprising a pair of vertical members 19 secured at their bottom ends to the carriage frame member 2 and interconnected -at their top ends by a cross member 20. A companion pair of vertical members 21 are similarly secured to the carriage frame member 3 and both pairs are interconnected at their top ends by a cross beam 22. Both pairs of vertical members 19 and 21 are advantageously made of angle iron and thus serve as a vertical guide for a tong carrier comprising a horizontal frame made up of two parallel longitudinal members 26 and 27 interconnected at both their ends by cross plates 28 and provided at each corner with a vertical guide post 30 made of angle iron and suitably braced -as at 31. These corner posts t within the vertical angle iron members 19 and 21 and guide as well as stabilize vertical movement of the tong carrier frame relative to the vertical members. To strengthen the tong carrier against deflection throughout its length, I provide at least one truss 31 secured at -both of its ends to vertical plates 32 and 33 secured to the guide posts :30 and supported intermediate its ends by posts 34.

For raising or lowering the tong carrier within the vertical members 19 and 21 and relative to the green concrete 16 being dealt with, I provide a liuid motor at each end of the transverse frame 18. Each motor comprises -a cylinder 35 attached as at 136 at its top end to its respective cross member 20 of the frame 18. A piston (not shown) Within the cylinder is connected at 37 by a rod 38 to its respective cross plate 28 of the tong carrier. Fluid under pressure from a pump 40 is delivered through suitable tubing as shown and lirst and second control valves 41 and 42 to the top and bottom interior respectively of the cylinders 35, from the cylinders to a reservoir 43, and from the reservoir back to the intake side of the pump.

Fixedly secured to and depending from the longitudinal members 26 and 27 of the tong carrier at uniformly spaced intervals are forwardly and rearwardly aligned tongs 45 .each recessed at its bottom end as at 46 to substantially match the recessed bottom end 47 of movable tongs 43 and 49 pivotally yattached as at Si) to the longitudinal members 26 and 27. Above these pivot points the arms of the movable tongs converge inwardly and upwardly into a pivotal connection 51 through an arcuate slot 51A with an actuating beam 52 pivotally attached at one of its ends as at 53 `to one end of a link 54 whose opposite end is pivotally attached as 'at 55 to a lever arm 56. This lever arm is secured to a shaft 57 journalled through the vertic-al plates 32 `and 33.

The top end of the converging movable tong arms is provided with a handle 60 for convenience in spreading or opening each individual set of cooperating tongs into a dowel-receiving position as shown in dotted and broken lines in FIGURE 4. A tension spring 61 interconnects the top end of the tong arms with lthe actuating beam 52 for automatically closing the tongs into a dowel-gripping position as shown in full lines in FIGURES 2 and 4.

From the foregoing it will be apparent that the tong carrier loaded with dowels 64 Vgripped by the tongs as shown in lfull lines in FIGURES 2 and 4 and thereby held in parallel relation to each other can be thrust downwardly by the fluid pressure motors 35 upon manipulation of the control valves 41 and 42 to the down position to embed the dowels, as shown in broken lines in FIGURE 4 and full lines in FIGURE 2, within the concrete at the desired level, which in an 8 inch yield is 4 inches from the top surface.

For simultaneously opening all of the tongs into a dowel-releasing position as shown in broken lines in FIG- URE 4 upon completion of the embedding operation I provide a hand lever 67 secured at one end of its ends to the shaft 57. Rotation of this shaft in a counter-clockwise direction by an upward swing of the hand lever 67 will, through the medium of the link 54 and lever arm 55, pullthe actuating beam 52 to the left and the movable ltongs 48about their pivot points 50 into the dottedand broken line positions as shown. Following this both control valves 41fand 42 aremanipulated to the up position to reverse the fluid pressure motors 35 fand thereby withdraw the tongs from the concrete by raising the tong carrier to .its original elevated position. To maint-ain the tongs in their open position during removal from the concrete, after depositing the dowels therein, Iprovide a latch 70 pivoted as 'at' 71 to the hand lever 67 and movable into engagement with a detent 72 by a trigger 73-and a link 74. The detent is secured to the top end of yan arm 75 vsecured to one of the longitudinal members 26 of the tong carrier frame. YUpon release of the hand lever and its return to the full line position shown inV FIGURES 2 and4, the tongs will again be free to be individually manipulated and spread at their bottom ends into a dowel-reloadingposition.

A supply of dowels `64 is-stored in a forward receptacle 8Gv and after removal therefrom are completely coated with grease and pas/sed by a workman to arearward dispensing receptacle '81 from which they are .withdrawn as needed-for the tong-loading operation.

The extent of the downward thrust of the dowel carrier and hence the depth of dowel penetration into the concrete can be controlled by vertically adjustable limitV stops in the form of bolts 8S carried by the frame member 26 and provided with lock nuts 86.

Grea'sing of the dowels is an important step in the method practiced in constructing a paved highway or similar surface with the m-achine of the present invention in sequential cooperation ywith those shown in my co-pendng applications covering Road Construction and Method of Producing, Machine for Transporting and Progressively Embedding Reinforcing Steelin Road Paving, and a Machine for Grooving Road Paving to Receive Expansion Strips. The method of the present `invention consists in the steps of embedding the' greased dowels as -aforesaid within the green concrete at intervals of, for example, 6'1v lineal feet, and' precisely at a depth of 4 inches in an S inch yield or atthe lexact center' of any other yield, `and the spacing of thedowels in parallel relation to each other at spaced apart intervals entirely across the roadway. `'I-hegreasing 4of the dowels prevents theirv adhesion to the concrete after `insertion, and the accommodating raligned holes formed by the insertion serve as slide bearings for the adjacent ends dominant features of the invention, such as the dowel carrier, its supporting frame and otherrelated parts, including the motor cylinders, could be assembled into a unitary device adapted for' attachment to any desired self-propelled machine in attain of road paving machinery.

While I have shown a particular form of embodiment of myY inventionl I am aware that many minor changes therein will readily suggest themselves tofothers skilled in the art without departing .from the spirit and scope of the invention. Having thus described my invention what I claim las new and desirezto protect by Letters Patent is:

Amachine .for use in surface. paving operations wherein the paving comprises cementitious material temporarily in la pl-astic state and confined within forms, said machine ,comprising in combination a self-propelled vehicle adapted to be supported upon the forms and movable ytherealong, vertical guide frames secured to and extending upwardly from the sides of saidk vehicle, a horizontal tong frame vertically slidable within said guide frames, a duid motor attached to each of said .guide frames and to the ends of said tong frame for raising and lowering the tong frame relative to said paving material, spacedapart pairs of fixed tong members secured to and depending from said tong yframe in lforward and rearward alignment with each other, companion pairs of tong members pivotally attached'to said tong frame and extending upwardly therefrom, the bottom end of each pair of Vfixed tong members and their companion tong members adapted to releasably gripr dowel bars for embedding the same in said paving material, a tong-actuating beam elevated from saidtong frame Vand-mountedV for reciprocal longitudinal movement relative thereto,

' said actuating beam hav-ing substantiallyelongated slots therein s lidably attaching the upper ends of said movable tongs to said-actuating beam, individual resilient means interconnecting thetop ends of eachV pair of said pivoted tong members and said actuating beam to knormally maintain said- .tong members in, dowel-grippingpositions ofV the concrete' sections in their lineal movement relav t-i-ve lto-each lother.

It is well knownv thatI Iconcrete poured-and leveled in theV conventional-manner as` -a 'roadway' or 'as any other at surface to lany extent will leventually crack in "an unpredictable, uncontrollable yzigzag -rnanner dueto expansion in response to periodic rising atmospheric temperawhereby -said tQng; members may, be manually individually opened:into4 dowel-receiving positions andvmanually operabley means-.carriedg-bythe.- tong frame and connested` to said actuating beam at one end thereof for im.- partng lateral movement to the Vactuating beam in one directionto,open said tong members into dowel-releasing positions;A

References Cited in theflle of this; patent srAII-TS. PATENTS AOTHER REFERENCES Introduction toA Highway Engineering, -fth edition, gSr John Wiley and Sons, Inc., New York, page 

